Quick Links

Banker Lab

Nearly every aspect of neuronal signaling depends on the accurate delivery of membrane proteins from the cell body, where they are made, to the axon or dendrites, where they carry out their specific functions. Normal synaptic function depends on a continuous supply of materials from the nerve cell body and neuronal survival depends on the retrograde transport of trophic signaling complexes. The extreme dimensions of nerve cells render them particularly susceptible to disorders that interfere with the long-range transport of membrane proteins. Mutations in motor proteins and motor-cargo linkers can lead to axonopathy and neuronal degeneration in mouse models and in human disease.

In previous work, we identified the principal trafficking pathways that underlie the polarized localization of neuronal plasma membrane proteins in cultured hippocampal neurons and developed methods to image each of the different populations of the long-range carriers that transport proteins along these pathways. Our results show that the selectivity of anterograde, kinesin-mediated transport plays a central role in the targeting of polarized proteins. Carriers containing dendritic proteins are transported into dendrites but excluded from axons; carriers containing axonal proteins enter both dendrites and axons, but are transported preferentially into axons. We have also developed assays to assess the selective transport of constitutively active kinesin motor domains in the absence of cargo.

Using the unique methods we have developed, we are now working to identify the kinesins that transport each population of long-range carriers and to investigate the molecular features of kinesins and the molecular modifications of microtubules that determine the selectivity of carrier transport. Our strategy uses two-color imaging to identify the carrier populations that are labeled by expressed GFP-tagged kinesins in combination with RNAi to inhibit the expression of individual kinesins and evaluate which populations of long-range carriers are affected. We are also investigating the selectivity of motor domain translocation for all kinesin organelle motors expressed in hippocampal neurons and examining how posttranslational modifications of tubulin influence the selectivity of motor domain transport and the transport of long-range carriers.

The methods we have developed to image axonal and dendritic transport also hold great promise to discover how disease processes affect transport. As a test case, we are presently using imaging methods to determine whether there are transport defects in nerve cells cultured from knock-in mice expressing abnormal Huntington’s disease protein. In a collaborative project with Dennis Bourdette, Mike Forte, and Jim Rosenbaum, we plan to extend this work to evaluate transport in animal models of axonal injury, such as occurs in multiple sclerosis, and to develop methods to image axonal transport in intact nervous tissue.

Personnel

Gary Banker
B.S., University of Washington
Ph.D., University of California at Irvine, 1973

Dr. Banker is a Senior Scientist in the Jungers Center and is a Professor of Neurology at OHSU. Gary received his B.S. degree from the University of Washington and a Ph.D. in neuroscience from the University of California at Irvine. Following postdoctoral training at Washington University, he held faculty positions at Albany Medical College and the University of Virginia before joining Oregon Health and Science University in 1998. He also serves as director of OHSU's Multidisciplinary Neuroscience Training Program. His research focuses on the development and maintenance of neuronal polarity, using novel methods developed by his lab for visualizing protein trafficking in living neurons in culture. Current projects aim to elucidate the molecular machinery that underlies the fidelity of protein targeting in nerve cells and how disruptions in this process lead to neural disease.

Marvin Bentley
Ph.D., University of Montana

My primary research interest is in all forms of vesicular trafficking. During my doctoral research at the University of Montana, I studied Endoplasmic Reticulum to Golgi transport, with a particular focus on the formation of the intermediate compartment. My work focused on calcium-mediated regulation of COPII vesicle transport and sorting. I joined the Banker laboratory to focus on post-Golgi transport in neurons.

Polarized neurons are essential for normal function of the nervous system and directed vesicle transport maintains this specialized cellular architecture. However, the underlying mechanism that produces this polarized transport is not very well understood. I am interested in the roles of kinesin motors and microtubules in selective transport. As my tools I use advanced live cell microscopy as well as super-resolution microscopy to understand the fundamental mechanisms underlying neuronal polarization.

I earned my bachelor degree in pharmaceutics and my master's degree in neuroscience and then joined the laboratory of Neurodegenerative Diseases at the Federal University of Rio de Janeiro to pursue a PhD. My project focused on synaptic dysfunction induced by Abeta oligomers - neurotoxins involved in the pathology of Alzheimer's Disease. Part of my doctoral research was conducted at Simon Fraser University where I identified a mechanism responsible for the impairment of organelle transport induced by these oligomers.

After completing my PhD, I joined the Banker lab seeking further understanding of the molecular mechanisms underlying the targeting and trafficking of proteins. Using the McDonald Fellowship from Multiple Sclerosis International Federation (MSIF), my study aims to identify motor proteins that transport each of the major organelle populations and test if these motors are differentially sensitive to reactive oxygen species (ROS).

Cheng Fang
M.S., Nanjing University
Ph.D., Pennsylvania State University

After I got my bachelor degree in pharmaceutics and my master's degree in biochemistry majoring in cancer biology from Nanjing University, I came to the United States to pursue my passion for biology. During my graduate training in Penn State University, I studied the lipid modification of GABAA receptors and its implication in anxiety and depression. After my PhD degree, and fascinated by the complexity of the brain and driven to understand more about neuropathological diseases, I joined the Banker lab for my postdoctoral training. We combine live cell imaging and nanotechnology to examine the axonal transport deficit in a Huntington's disease model and work on building an automated system for future drug screen for HD or other neurodegenerative diseases.

I am a visiting scientist in the Banker lab, although I should be called a "revisiting" scientist! I completed my PhD in Dr. Banker's lab in 2005, using dual-color live cell imaging to study how newly-synthesized polarized proteins are sorted into vesicular carriers as they exit the Golgi complex. During my thesis work, I became very interested in using such live imaging techniques to observe membrane trafficking events in an intact organism. To this end, I did a postdoctoral fellowship with Dr. Teresa Nicolson, whose lab uses the zebrafish as a model organism to study hearing and balance.

I am currently doing a second postdoctoral fellowship at Lewis and Clark College, where I am learning how to be a good professor, and also doing research with Dr. Janis Lochner. Her lab studies the synaptic release of the neuromodulators Tissue Plasminogen Activator and Brain-Derived Neurotrophic Factor in cultured hippocampal neurons. In the future, I plan to combine these research experiences, and study the vesicular trafficking of synaptic proteins in live zebrafish larvae.

Brian Jenkins
B.S., University of California at San Diego

I graduated from UCSD with a BS in molecular biology. Thereafter, I was employed as a research technician at Scripps Research Institute where I assisted in characterizing a mouse model of neurodegeneration involving a novel E3 ubiquitin ligase and studied neuronal cytoskeleton proteins that contribute to neurite outgrowth. Currently, I am a graduate student in the lab investigating the kinesin-cargo relationship and its role in selective transport of membrane trafficking in cultured hippocampal neurons.

Julie Luisi
B.S., Montana State
A.A.S. (biotechnology), Portland Community College

I joined the Banker lab in the spring of 1999 with a Bachelor's degree in General Biology (Botany emphasis) from Montana State University and an Associate's degree (yes, after the Bachelor's) in Biotechnology from Portland Community College. I am currently a Senior Research Assistant. In addition to keeping the lab organized and well stocked, my primary responsibility is to design and construct the plasmids that my colleagues use to image GFP-tagged proteins in nerve cells.

Barbara SmoodyB.A., University of Oregon, 1981

Everyone in the Banker lab uses neuronal cultures for their experiments—and I am the one who prepares those cultures. Since joining the lab in January 2000 as a Senior Research Assistant, I have made hundreds of cultures and apparently get it right often enough to keep all of my colleagues occupied and productive (and to make the images you'll see on the website). I have worked in labs on Marquam Hill for 27 years, at OHSU and Shriner's Hospital Research. I earned a BA in Biology from the Robert D. Clark Honors College at the University of Oregon.